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pitchpipe writes "A puzzling pattern in the cosmic rays bombarding Earth from space has been discovered by an experiment buried deep under the ice of Antarctica. ... It turns out these particles are not arriving uniformly from all directions. The new study detected an overabundance of cosmic rays coming from one part of the sky, and a lack of cosmic rays coming from another." The map of this uneven distribution comes from the IceCube neutrino observatory last mentioned several days ago.

It would be great if they'd actually found the center of the universe, in contradiction to all previous theories, since that would allow a hole in relativity that you might be able to squeeze FTL through. At least as far as i understand it some methods of FTL would be non-paradoxical if there was actually a universal reference frame instead of everything being, well, relative.

Unfortunately i'm sure there's a much more mundane explanation for the phenomenon which they will eventually discover.

I'm not sure where you got the idea that i think the universe must have a center. I would like it if it _did_ have a center, or at least something that would serve as a reference point, so that certain kinds of FTL would be possible (again, if i'm understanding the theory) but i never said that it had to. And i concluded by saying that they'll probably find this phenomenon is evidence of something else entirely. So i'm really not sure what you're on about.

if you freeze time, every single piece of matter in the universe will be fixed in a single position. every single piece of matter can be 'reached' from every other piece of matter, though you'd have to travel for billions of years to get to some (remember time has stopped, so inflation has ceased). thus, every piece of matter could be given an xyz coordinate relative to the first piece of matter you decide to start measuring from.

you plot every xyz coordinate of every piece of matter in the universe. you will end up with a shape, no matter how odd it looks (donut, blob, square, pyramid, who cares). that shape has a center, which is the average of all xyz coordinates.

This would be true only if the universe had an euclidean geometry.

This is hard to visualize in three dimensions, so let's start with a two-dimensional case. Imagine a perfectly flat horizontal surface. Any triangle you draw in that surface will have three internal angles that add up to 180 degrees. If you draw any finite number of points there you could take the average of the xy coordinates and define a "center" for that set of points.

Now imagine a curved surface, let's say the surface of the earth. Define a triangle like this: point A is at zero latitude, zero longitude. Point B is at zero latitude, 90 degrees West longitude. Point C is at the North Pole. This triangle has three angles of ninety degrees, adding up to 270 degrees.

How would you define a "center" for a set of points randomly distributed over the surface of the earth? You could do it only if those points were sufficiently close together so the surface between them could be approximated by a flat surface. You can talk about the center of a continent, but the center of the whole surface of the earth is undefined.

Imagine the same problem in a universe with three dimensions that's curved in a fourth dimension and you will understand a bit of what general relativity is all about.

Imagine the same problem in a universe with three dimensions that's curved in a fourth dimension and you will understand a bit of what general relativity is all about.

More like a pseudo-understanding. It's a bad analogy. The fourth dimension is not spatial. It's temporal [wikipedia.org]. It was mathematically convenient to place time on the graph simultaneously. It also happens to reflect what special relativity indicates is the reality: that space and time are not independent. However time is not really the fourth dimension in the way that people usually think of it, in the way that a tesseract [wikipedia.org] is a four dimensional object, an object that can only be correctly measured using 4 spatial

You mean the fourth coordinate you use in Minkowski's formulae is temporal. Nobody is forced to ordinalize the dimensions used in their conceptual models by any given standard. For example, I learned coordinate systems from programming a TI-99/4a computer that addressed screen characters in "row/column" format. This became a stumbling block for me learning the cartesian (x,y) coordinate system, I kept wanting to notate the Y before the X. Their "first" dimention was my "second".

But as far as I know, the question is still unresolved. If space is curved in on itself, we could in fact go (with a spacecraft) a finite distance in one direction and arrive back where we started. If not, we'd just go on and on forever, at one point our spacecraft would overtake the current extent of matter and we'd pass into unoccupied space where the only thing left is radiation from the (slow) matter-filled part.

So the universe has no center is space is curved, but then only if the curvature is smaller

By your definition center of the universe is you. There is a real, scientific explanation for this fact, but I'm too lazy to explain it to you. Just check out what "our universe" and "a single slice of time" means in context of relativity.

All of this is presuming that the rapid expansion phase of the Big Bang is in fact reality and that the Big Bang theory is in fact the correct cosmological theory for the origin of the universe.

Mind you, I'm not disputing the conclusion here nor even that this is the prevailing theory for the universe, but there are some postulates and presumptions to your discussion here which are unstated. With those presumptions, you are correct.

I'll admit that discovering a "center" to the universe would create some ve

"to find a level of mechanics that would "overthrow" Einstein's relativity equations with something else (likely more complex still)."

I would contend that to properly 'overthrow' Einstein's relativity would require something much simpler. Einstein plus Newton is pretty accurate. To get more accurate you'd have to get closer to correct, Occam's Razor dictates that correct would need to be a simpler solution, not a more complex one.

There is nothing even close to simple or elegant about the current highly comp

Nice discussion with mods voting (not moderating) the people who defend their favorite _theories_.

Just remember that when you're discussing the universe, you have to reference the universe. When you are referencing the universe then you have to keep it in the bounds of what we considder a universe. What we considder a universe is what is both inside logic and what defines logic.

Currently there is some discussion about the correct logic. What can be proven? Unless you have infinity at your disposal and follo

I'll say it's a fair mod, and it was me that was modded troll. It's my bad luck to get a moderator who's got a poor sense of humor and also knows his stuff. I was going for funny, but the line between funny and troll is rather thin. Those darned astrophysicists are so darned literal, I should have expected it being as how this is slashdot and all.

I've complained about the moderation here before and there's a time for that, but this isn't one of those times.

Wait, what!? You are saying that the post before mine deserved being modded a troll, when it provides new ideas and arguments that apply to the side discussion, but then address moderators and tell them to not jump the gun and mod something as off topic when it provides new information on a side discussion?

Which is it?

This is the first time that I've seen someone claiming that space is curved and that some parts of the universe have effectively lost to us is modded as a troll... and defended as a troll.

Not that part. The part about Time being bi-curious (an allusion to variability/multidimsionality of time), the part about spacetime being potentially non-contiguous (unprovable at best), the part about stuff outside our light cone being outside our universe rather than just out of reach (the crux of a long-running religious flamewar). When I wrote that I knew I was trollin', and throwing all three into one post was unsubtle. I was just hoping to catch a moderator who thought it was funny, or a fellow sl

Unfortunately i'm sure there's a much more mundane explanation for the phenomenon which they will eventually discover.

You are probably right.

However when I read an article like this one, I do wonder what sort of interstellar drive would produce an exhaust or wake with these kinds of characteristics? It seems to me that today's astronomical discussions should include some comments on the possibility that what is being observed out there might not be a natural phenomenon.

Oh, I know what is going on. With all the earthquakes, floods, oil well leaks and explosions, global warming. Those aren't any ordinary cosmic rays, they are Mongo Rays! Lord Ming has it in for us. Where is Flash and Dr. Zarkov when we need them?

I'm happy that it was phrased in the form of a question. Too often, the reaction to a bit of science that somebody doesn't wish to believe is simply rejection of it, perhaps combined with unsourced assertions (or assertions to un-peer-reviewed sources).

You don't have to know everything in science. There's too much to know. Ignorance is fine, as long as you're (a) aware of it, (b) curious, and (c) not going to fight against those who do know it.

You must be new around these parts. Despite Slashdot's self image as a haven of the extremely smart and well educated... it's really not much better than any other random collection of people. A few at one end of the bell curve, a few at the other, and the bulk huddled comfortably under the hump in the middle. Only nowadays, with education (both formal and self) being rare - what's under the hump isn't all that remarkable.Somehow there has arisen

No it isn't. The Earth's magnetic field has negligible effect on cosmic rays: they are far to energetic for it to influence them significantly. What protects us from cosmic rays is the atmosphere.

There is a link between solar activity and cosmic rays and of course there is the interaction of the solar wind and our magnetic field, so in theory there is a pathway between cosmic rays and the Earth's magnetic field.

... that should, of course, be "the _less_ solar activity, the more cosmic rays"

This is one of the good-fit hypothesises with regards to so-called "global warming". Less active sun = more cosmic rays = more clouds = less heat.

The warming would then come from the combined effects of the solar cycles in the latter part of the 20th century which were the strongest in recorded history. The difference from currently debunked solar theories is that it's not the TSI (visible solar output) that effects the climate,

No it isn't. The Earth's magnetic field has negligible effect on cosmic rays: they are far to energetic for it to influence them significantly. What protects us from cosmic rays is the atmosphere.

This is incorrect. The International Space Station has a significantly lower cosmic radiation environment due to the Earth's magnetic field. However, the cosmic rays that are energetic enough to be detected under a few hundred meters of ice can easily punch through the Earth's magnetic field.

Celestial bodies do not surround us. The sun and the moon together cover less than 1/100,000th of the sky.

Indeed. The heliosphere might, due to its vast size (and its shock interaction with the galactic medium is apparently a known source of cosmic rays), be an intermediate filter with enough pull to distort the path of incoming cosmic rays.

The International Space Station has a significantly lower cosmic radiation environment due to the Earth's magnetic field.

The Earth's magnetic field shields it from solar "cosmic" rays and probably some secondary galactic ones. The primaries, however, are so energetic that they are merely deflected a bit. What does stop a lot of primaries is the field embedded in the solar wind. Since the heliosphere is asymmetric and poorly mapped this may very well account for the observed asymmetry.
I concede that

Celestial bodies do not surround us. The sun and the moon together cover less than 1/100,000th of the sky.

Really? so you are saying the universe is flat, and the earth is off in a corner where nothing but the sun and moon are around it?

Seems to me, that the universe is in at least 3 Dimensions, and no matter which direction we go, we are going to hit some "celestial" body.

And considering Celestial bodies means naturally occurring physical entities, associations or structures that current science has demonstrated to exist in outer space, but not including earth, seems that maybe your a bit wrong on your last pa

> Seems to me, that the universe is in at least 3 Dimensions, and no matter> which direction we go, we are going to hit some "celestial" body.

Since all but a negligible fraction of all the celestial bodies in the universe are stars that would mean that the entire sky would glow at the surface temperature of the average star since no matter where you looked you would be looking directly at the surface of a star.

Really? so you are saying the universe is flat, and the earth is off in a corner where nothing but the sun and moon are around it?

Is the sky flat where you live?

"and no matter which direction we go, we are going to hit some "celestial" body."

Nope, space is pretty much just space. Galaxies commonly collide with each other but the stars within those collisions very rarely smash into each other. It's not that there is any shortage of celestial bodies it's just that space is really, really, big.

There's also the fact that ALL of the celestial bodies are contained within the microwave background, so why is it that we can see the microwave background if every direction is obscured with a celestial body?

R'lyeh is in the south pacific. Pnakoticos is in the Australian desert. Irem is in Saudia Arabia. Unfortunately, the Pentagonally Symmetrical Elder Things named their last surface city 'Can'ned'spham', which is why the Shoggoths ate them.

R'lyeh is in the south pacific. Pnakoticos is in the Australian desert. Irem is in Saudia Arabia. Unfortunately, the Pentagonally Symmetrical Elder Things named their last surface city 'Can'ned'spham', which is why the Shoggoths ate them.

I looked at the image and the cosmic rays seem to be lacking only in a small area of the whole measurement. Maybe somebody in a galaxy far far away is blocking the cosmic rays en masse with a bunch of these: http://en.wikipedia.org/wiki/Dyson_sphere [wikipedia.org] (as in colonization of one or multiple galaxies).

Maybe somebody in a galaxy far far away is blocking the cosmic rays en masse with a bunch of these: http://en.wikipedia.org/wiki/Dyson_sphere [wikipedia.org] (as in colonization of one or multiple galaxies).

We know about these remote stars and galaxies because we can see them, which means they're not in a Dyson sphere.

As far as I can tell from reading the article, this proves that cosmic rays distribution does not follow a truly random pattern as they hit earth. Given that these rays originate from stars/nova/events and these events are not randomly distributed in the universe, why is this a surprise? I can only guess someone has theorised that if the universe is infinitely big, then the cosmic ray distribution should tend towards perfect (infinite) randomness. Can anyone shed light on the theory that this finding is dip

I love Look Around You. It's a nonsense-filled educational program spoof about science. Cartoon Network showed the second season in their Adult Swim lineup a couple years ago. The first and second seasons have different formats and intros and music, and the "next episode" bits allude to shows that don't exist. Series 1 episodes are shorter and more abstract "in the classroom" type videos. Series 2 are longer format docu

Except that the detector is for detecting neutrinos. They have no charge. Not only that but they are not expected to interact with the earth's magnetic fields according to the current theory. If only there were some sort of "article" that might have this kind of information in a form that is easy to "read" with a convenient "hyper-link" to lead us to it.

Sheesh... if only we had some sort of "moderators" who might understand this. "interesting" my ass.

While it's true that IceCube is designed to be a neutrino telescope, the observations here involve more common and easier to detect cosmic rays (e.g. gamma rays), coming from the southern half of the sky.

See, when IceCube is looking for neutrinos, they look for signals coming from beneath the northern part of the sky. They are essentially using the entire planet earth as a filter for cosmic rays since they can't pass through that much solid material, while neutrinos can with ease. Neutrinos don't interact

...neutrinos... have no charge... are not expected to interact with the earth's magnetic fields according to the current theory.

Oh. Well, if it's according to current theory, that's OK then.
For 30 some years of my life, I was told (by current theory) they were massless. Matter of fact, current theory still doesn't have a good number for neutrino mass.

While the Standard Model might have a lot in the way of predictive power, it doesn't have a lot in the way of explanatory power. How about you just add